// this function is needed to work around
// a bug in IE related to element attributes
function hasClass(obj) {
    var result = false;
    if (obj.getAttributeNode("class") != null) {
        result = obj.getAttributeNode("class").value;
    }
    return result;
}

function stripe(id) {

    // the flag we'll use to keep track of
    // whether the current row is odd or even
    var even = true;

    // obtain a reference to the desired table
    // if no such table exists, abort
    var table = document.getElementById(id);
    if (! table) {
        return;
    }

    // by definition, tables can have more than one tbody
    // element, so we'll have to get the list of child
    // &lt;tbody&gt;s
    var tbodies = table.getElementsByTagName("tbody");

    // and iterate through them...
    for (var h = 0; h < tbodies.length; h++) {

        // find all the &lt;tr&gt; elements...
        var trs = tbodies[h].getElementsByTagName("tr");

        // ... and iterate through them
        for (var i = 0; i < trs.length; i++) {
            var mytr = trs[i];

            if (even) {
                var style = mytr.getAttribute("class");
                if (style != null) {
                    style += " even";
                } else {
                    style = "even";
                }
                mytr.setAttribute("class", style);
            }

            // flip from odd to even, or vice-versa
            even =  ! even;
        }
    }
}